She’s had multiple surgeries, tried all the recommended treatments for her disorder and sits twice weekly for intravenous infusions.

Tonani, 38, decided several years ago to try pot. And it has worked for her, she said, especially strains low in the psychedelic chemical THC and high in the non-psychoactive ingredient cannabidiol, known as CBD.

As a medical marijuana patient, Tonani knows it can be hard to find the rare strains that don’t make you high - and it can be even harder to get the same kind of pot consistently.

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Testing shows that some marijuana strains are not what they purport to be in name, chemical content and genetics. This is particularly concerning for patients seeking pot low in intoxicants and high in pain-relief or other therapeutic qualities.

One strain widely known for its high-CBD and popular among medical marijuana patients is called Harlequin. But when Tonani and a leading Seattle pot-testing lab analyzed 22 samples of Harlequin from various growers and dispensaries, five of them were high in THC and had virtually no CBD, which means people trying to take medicine were just getting high instead.

Misnaming and inconsistent chemical profiles are extremely common, said Dr. Michelle Sexton, a naturopath, founder of PhytaLAB and an adviser to the state Liquor Control Board.

This problem can be significant for patients who don’t want to be stoned while working or behind the wheel. It’s even more so for pediatric patients. “You don’t want a 6-year-old with epilepsy being put on a bus under the influence of a psychedelic chemical,” Tonani said.

And there’s this irony: Recreational pot users will soon have greater assurances about the safety and chemical content of the pot they buy at retail stores in the state’s new legal pot system than the best-educated patients have in the largely unregulated medical system, where testing and accurate labeling are not mandated for dispensaries.

“It’s completely backwards from what it should be,” said Randy Oliver, chief scientist at Analytical 360, the lab that collaborated with Tonani’s firm on the research.

Alison Holcomb, chief author of Initiative 502, which legalized adult possession of marijuana, noted that I-502 is not - as many call it - a recreational pot law. Its requirement that all products display THC and CBD content is likely to make medical patients more informed.

“It creates a legal marijuana market. The requirements apply equally to all marijuana that is being used, whatever the purpose of consumption,” said Holcomb, director of criminal justice for the ACLU of Washington state.

There’s still some mystery, due to a lack of scientific research, about how certain chemicals in pot impact different people.

But there’s enough evidence about the anticonvulsant qualities of CBD that the federal government’s only pot-growing facility plans to produce up to 600 kilos of high-CBD marijuana for study.

“The whole thing is just so loose and unregulated,” said Dr. Mahmoud ElSohly, director of the Marijuana Research Project at the University of Mississippi, about medical marijuana in states such as Washington. ElSohly’s goal is to grow high-CBD pot, with a very consistent chemical profile so it can be used in standardized research.

Since she’s been using pot, Tonani said, friends, family and other patients have queried her about what to use and where to get it. About a year ago, she said, she really came to understand dramatic differences in the quality of dispensaries and in marijuana called the same name.

That led her to form Verda Bio, a company devoted to researching the genetics and therapeutic uses of marijuana.

Tonani began collaborating with Analytical 360, which encourages transparency in the industry by posting on its website the results of all testing the lab has done on samples in the past 60 days.

She went out and bought five samples of Harlequin at Seattle-area dispensaries. Four of the samples varied considerably in their potency of THC and CBD. Even though they all had roughly a 2-to-1 ratio of CBD to THC, their variations in potency would make consistent dosing difficult. A fifth sample was radically different, with almost no CBD and high THC.

Tonani’s findings essentially matched an analysis by Analytical 360 of 17 samples called Harlequin it tested recently. Four of the samples were nothing like Harlequin.

Further DNA tests by Tonani on two of the samples she acquired showed that they were not even genetically similar.

Experts cite a number of reasons for such inconsistencies.

One may be the lack of testing standards for labs analyzing medical marijuana, Sexton said. It’s a problem addressed by I-502 rules, which set requirements for accredited labs.

Another likely culprit is genetics. When growing from seeds - and not carefully cultivated clippings - there’s a possibility of variation in the plant’s chemical profile because of dominant and recessive genes, said breeder Chris Kelly, CEO of Seattle’s Green LionFarms, and Seattle grower Jerry Whiting, co-owner of LeBlanc CNE, growers and brokers of medical marijuana.

Age also could be a factor, even when growing from clippings. The mother plants can lose their vigor over time, just as elderly people would.

Human error, such as the mislabeling of clippings, also could be to blame. Labels fall off and often get misplaced, Sexton said.

Lastly, growers and sellers could be engaging in fraud, calling something Harlequin because they think it will sell better or command a higher price.